Mali 01: Pilot Study of CD4+ T Cell Immune Responses to Mycobacterium Tuberculosis. The protocol was closed to new enrollment on December 31st 2008. Completion of follow up visits remains. The last patient is scheduled to complete the study in December 2009. Mali 02: Establishment of Normal Parameters for Blood and Sputum with Samples Obtained From Volunteers in Bamako Ongoing Mali 03: Correlation of the Precursor Frequency of CD4 + Effector Memory T cells with Induration measured in the Tuberculin Skin Test (TST) Enrolled. The goal is to complete this protocol in 2009. Mali 04: A Cohort Observational Study to Assess the Virologic Response to Standard HIV Treatment in Bamako, Mali Commenced December 2008. Enrolling. The goal is to complete this protocol in 2009. Interim data has been presented in abstracts;manuscripts are in preparation.